Conventionally, communication terminals, such as a touch-tone fixed telephone, a facsimile and a mobile phone with a numeric keypad, generally have a so-called phonebook function that enables registration of persons' names and their phone numbers in the communication terminals. However, as the number of registered phone numbers increases, an increased number of steps are required when making a phone call to select a person whom a user wants to call. Therefore, many of such communication devices have an additional function to quickly call a certain person in a small number of steps.
One way to achieve the function of enabling a quick phone call is a method (Method 1) of calling a pre-registered phone number (called party's phone number) by pressing and holding a certain key. Another way to achieve the function is a method (Method 2) of making a phone call to a called party by inputting a one-digit or two-digit number previously registered in association with the called party's phone number. A method for realizing the function of enabling a quick phone call in a small number of steps in such a manner is called “abbreviated dialing” or “speed dialing” etc.
Recently, communication terminals with no numeric keypad for number/text input, such as smartphones, have been increasingly used. Such a communication terminal with no numeric keypad includes a touch panel to display an operation screen which is operable by directly touching it.
Many of these communication terminals carry out text input in the following manner, as disclosed in, for example, Patent Literature 1. That is, five Japanese Kana characters are associated with each key of a software keyboard displayed on the touch panel. By selecting a key by touching the touch panel with, for example, a stylus and thereafter moving the stylus upward, downward, rightward or leftward while still touching the touch panel (i.e., so-called flick input), a Kana character previously associated with the direction of the movement is selected. Such an input method has become a common way of text input into communication terminals.
These communication terminals which include a touch panel operable by touching an operation screen can have the following method (Method 3) in order to achieve the above-mentioned function of making a quick phone call. That is, for example, a shortcut is created on the operation screen which enables a one-touch dialing to a called party, and a phone call to the called party can be made by selecting the shortcut.
Furthermore, Patent Literature 2 discloses a telephone that has the following function (Method 4) of making a quick phone call. That is, by drawing a stroke on a tablet, a corresponding gesture is entered and a phone number associated with the gesture is called (calling process).